High-throughput roll-to-roll processing could be used to scale up the manufacture of flexible thermoelectric generators. Very thin thermoelectric layers can be manufactured at high throughput speed and low cost and, most importantly, are predicted to possess better thermoelectric properties than thicker layers. Here we present a study on a series of bismuth telluride films of different thickness (few nm to 370 nm), deposited on polymer substrates at room temperature using DC magnetron sputtering. Unlike previous studies of deposition of bismuth telluride films onto heated substrates, an island-growth mode, indicated by AFM, was observed for Bi-Te films grown at room temperature. A period of growth in which the layer only partially coats the substrate, with only imperfect connections between islands, was observed. In this partially coated region, the coating exhibited an extremely high Seebeck coefficient. An energy barrier mechanism, similar to the interface effect in nanomaterials, is proposed to explain this phenomenon, along with a possible quantum confinement effect. We found that a thinner Bi-Te film could generate a greater power factor because of a quasi-decoupling of Seebeck coefficient and electrical resistivity. In addition, ensuring that the sample passed directly under the sputtering target, and using a substrate smoothed with an acrylate layer were found to improve film properties, thus enhancing thermoelectric behaviour.

高通量卷对卷处理可用于扩大柔性热电发电机的制造规模。可以以高生产速度和低成本来制造非常薄的热电层，并且最重要的是，据预测，与较厚的层相比，其具有更好的热电特性。在这里，我们介绍了一系列使用直流磁控溅射在室温下沉积在聚合物基板上的不同厚度（几纳米至370纳米）的碲化铋薄膜的研究。与先前关于将碲化铋薄膜沉积到加热的基材上的研究不同，对于室温下生长的Bi-Te薄膜，观察到由AFM表示的岛生长模式。观察到一个生长阶段，其中该层仅部分涂覆了基底，岛之间只有不完善的连接。在这个部分涂层的区域 该涂层表现出极高的塞贝克系数。提出了一种类似于纳米材料界面效应的能垒机制来解释这种现象以及可能的量子限制效应。我们发现，由于塞贝克系数和电阻率的准解耦，较薄的Bi-Te薄膜可以产生更大的功率因数。另外，发现确保样品直接通过溅射靶下方，并使用经丙烯酸酯层平滑的基材，可以改善膜性能，从而增强热电性能。我们发现，由于塞贝克系数和电阻率的准解耦，较薄的Bi-Te薄膜可以产生更大的功率因数。另外，发现确保样品直接通过溅射靶下方，并使用经丙烯酸酯层平滑的基材，可以改善膜性能，从而增强热电性能。我们发现，由于塞贝克系数和电阻率的准解耦，较薄的Bi-Te薄膜可以产生更大的功率因数。另外，发现确保样品直接通过溅射靶下方，并使用经丙烯酸酯层平滑的基板，可以改善膜性能，从而增强热电性能。